package org.example.lotterysystem.service.mq;

import cn.hutool.core.date.DateUtil;
import lombok.extern.slf4j.Slf4j;
import org.example.lotterysystem.common.exception.ServiceException;
import org.example.lotterysystem.common.utils.JacksonUtil;
import org.example.lotterysystem.common.utils.MailUtil;
import org.example.lotterysystem.common.utils.SMSUtil;
import org.example.lotterysystem.controller.param.DrawPrizeParam;
import org.example.lotterysystem.dao.dataobject.ActivityPrizeDO;
import org.example.lotterysystem.dao.dataobject.WinningRecordDO;
import org.example.lotterysystem.dao.mapper.ActivityPrizeMapper;
import org.example.lotterysystem.dao.mapper.WinningRecordMapper;
import org.example.lotterysystem.service.DrawPrizeService;
import org.example.lotterysystem.service.activitystatus.ActivityStatusManager;
import org.example.lotterysystem.service.dto.ConvertActivityStatusDTO;
import org.example.lotterysystem.service.enums.ActivityPrizeStatusEnum;
import org.example.lotterysystem.service.enums.ActivityPrizeTiersEnum;
import org.example.lotterysystem.service.enums.ActivityStatusEnum;
import org.example.lotterysystem.service.enums.ActivityUserStatusEnum;
import org.springframework.amqp.rabbit.annotation.RabbitHandler;
import org.springframework.amqp.rabbit.annotation.RabbitListener;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor;
import org.springframework.stereotype.Component;
import org.springframework.util.CollectionUtils;

import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;

import static org.example.lotterysystem.common.config.DirectRabbitConfig.QUEUE_NAME;

@Slf4j
@Component
@RabbitListener(queues = QUEUE_NAME)
public class MqReceiver {

    @Autowired
    private DrawPrizeService drawPrizeService;
    @Autowired
    private ActivityStatusManager activityStatusManager;
    @Qualifier("asyncServiceExecutor")
    @Autowired
    private ThreadPoolTaskExecutor threadPoolTaskExecutor;
    @Autowired
    private MailUtil mailUtil;
    @Autowired
    private SMSUtil smsUtil;
    @Autowired
    private ActivityPrizeMapper activityPrizeMapper;
    @Autowired
    private WinningRecordMapper winningRecordMapper;

    @RabbitHandler
    public void process(Map<String, String> message) throws Exception {
        //成功接收到队列中的消息
        log.info("MQ成功接收到消息 message: {}", JacksonUtil.writeValueAsString(message));
        String paramString = message.get("messageData");
        DrawPrizeParam param = JacksonUtil.readValue(paramString, DrawPrizeParam.class);
        //处理抽奖流程
        try {
            //校验抽奖请求是否有效
            if (!drawPrizeService.checkDrawPrizeParam(param)) {
                return;
            }
            //状态扭转处理
            statusConvert(param);
            //保存中奖者名单
            List<WinningRecordDO> winningRecordDOList = drawPrizeService.saveWinnerRecords(param);
            //通知中奖者(邮箱/短信)
            //异步(并发)处理
            syncExecute(winningRecordDOList);
        } catch (ServiceException e) {
            log.error("处理MQ消息异常!{}:{}",e.getCode(), e.getMessage(), e);
            //如果异常,需要保证事务一致性(回滚),抛出异常
            rollback(param);
            throw e;
        } catch (Exception e) {
            log.error("处理MQ消息异常!", e);
            //如果异常,需要保证事务一致性(回滚),抛出异常:消息重试
            rollback(param);
            throw e;
        }
    }

    //处理抽奖异常的回滚行为:恢复处理请求之前的库表状态
    private void rollback(DrawPrizeParam param) {
        //1.回滚状态:活动,奖品,人员
        //状态是否需要回滚
        if(!statusNeedRollback(param)) {
            //不需要
            return;
        }
        //需要回滚
        rollbackStatus(param);
        //2.回滚中奖者名单
        //状态是否需要回滚
        if(!winnerNeedRollback(param)) {
            //不需要
            return;
        }
        //需要回滚
        rollbackWinner(param);
    }

    //回滚中奖记录
    private void rollbackWinner(DrawPrizeParam param) {
        drawPrizeService.deleteRecords(param.getActivityId(), param.getPrizeId());
    }

    private boolean winnerNeedRollback(DrawPrizeParam param) {
        //判断活动中的奖品是否存在中奖者
        int count = winningRecordMapper.countByAPId(param.getActivityId(), param.getPrizeId());
        return count > 0;
    }

    //恢复相关状态
    private void rollbackStatus(DrawPrizeParam param) {
        //涉及状态的恢复工作
        ConvertActivityStatusDTO convertActivityStatusDTO = new ConvertActivityStatusDTO();
        convertActivityStatusDTO.setActivityId(param.getActivityId());
        convertActivityStatusDTO.setTargetActivityStatus(ActivityStatusEnum.RUNNING);
        convertActivityStatusDTO.setPrizeId(param.getPrizeId());
        convertActivityStatusDTO.setTargetPrzieStatus(ActivityPrizeStatusEnum.INIT);
        convertActivityStatusDTO.setUserIds(
                param.getWinnerList().stream().map(DrawPrizeParam.Winner::getUserId)
                        .collect(Collectors.toList())
        );
        convertActivityStatusDTO.setTargetUserStatus(ActivityUserStatusEnum.INIT);
        activityStatusManager.rollbackhandlerEvent(convertActivityStatusDTO);
    }

    private boolean statusNeedRollback(DrawPrizeParam param) {
        //扭转状态时,保证了事务的一致性,要么都扭转了,要么都没扭转(不包含活动)
        //因此,只需判断人员/奖品是否扭转过,就能判断出状态是否全部扭转
        //不能判断活动是否已经扭转
        ActivityPrizeDO activityPrizeDO = activityPrizeMapper.selectByAPId(param.getActivityId(), param.getPrizeId());
        if(activityPrizeDO.getStatus().equalsIgnoreCase(ActivityPrizeStatusEnum.COMPLETED.name())) {
            //已经扭转了,需要回滚
            return true;
        }
        return false;
    }

    //并发处理抽奖后续流程
    private void syncExecute(List<WinningRecordDO> winningRecordDOList) {
        //通过线程池
        //短信通知
        threadPoolTaskExecutor.execute(() -> sendMessage(winningRecordDOList));
        //邮件通知
        threadPoolTaskExecutor.execute(()->sendMail(winningRecordDOList));
    }

    //发邮件
    private void sendMail(List<WinningRecordDO> winningRecordDOList) {
        if (CollectionUtils.isEmpty(winningRecordDOList)) {
            log.info("中奖列表为空,不用发邮件");
            return;
        }
        for (WinningRecordDO winningRecordDO : winningRecordDOList) {
            String context = "Hi，" + winningRecordDO.getWinnerName() + "。恭喜你在"
                    + winningRecordDO.getActivityName() + "活动中获得"
                    + ActivityPrizeTiersEnum.forName(winningRecordDO.getPrizeTier()).getMessage()
                    + "：" + winningRecordDO.getPrizeName() + "。获奖时间为"
                    + DateUtil.formatTime(winningRecordDO.getWinningTime()) + "，请尽快领 取您的奖励！";
            mailUtil.sendSampleMail(winningRecordDO.getWinnerEmail(),
                    "中奖通知", context);
        }
    }

    //发短信
    private void sendMessage(List<WinningRecordDO> winningRecordDOList) {
        if (CollectionUtils.isEmpty(winningRecordDOList)) {
            log.info("中奖列表为空,不用发短信");
            return;
        }
        for (WinningRecordDO winningRecordDO : winningRecordDOList) {
            Map<String, String> map = new HashMap<>();
            map.put("name", winningRecordDO.getWinnerName());
            map.put("activityName", winningRecordDO.getActivityName());
            map.put("prizeTiers", ActivityPrizeTiersEnum.forName(winningRecordDO.getPrizeTier()).getMessage());
            map.put("prizeName", winningRecordDO.getPrizeName());
            map.put("winningTime", DateUtil.formatTime(winningRecordDO.getWinningTime()));
            smsUtil.sendMessage("SMS_471940038",
                    winningRecordDO.getWinnerPhoneNumber().getValue(),
                    JacksonUtil.writeValueAsString(map));
        }
    }

    //状态扭转
    //private void statusConvert(DrawPrizeParam param) {

        //问题:
        //1.活动状态扭转有依赖性,导致代码维护性差
        //2.状态扭转条件可能会扩展,当前写法扩展性差,维护性差
        //3.代码灵活性,扩展性,维护性极差
        //解决方案:设计模式(责任链,策略模式)


        //1.奖品 INIT->COMPLETED
        //查询活动关联的奖品信息
        //条件判断是否符合扭转奖品状态:判断当前状态是不是COMPLETED,如果不是,要扭转

        //2.人员列表 INIT->COMPLETED


        //3.活动 RUNNING->COMPLETED
        //全部奖品抽完之后才改变状态

        //更新缓存

    //}

    private void statusConvert(DrawPrizeParam param) {
        ConvertActivityStatusDTO convertActivityStatusDTO = new ConvertActivityStatusDTO();
        convertActivityStatusDTO.setActivityId(param.getActivityId());
        convertActivityStatusDTO.setTargetActivityStatus(ActivityStatusEnum.COMPLETED);
        convertActivityStatusDTO.setPrizeId(param.getPrizeId());
        convertActivityStatusDTO.setTargetPrzieStatus(ActivityPrizeStatusEnum.COMPLETED);
        convertActivityStatusDTO.setUserIds(param.getWinnerList().stream()
                .map(DrawPrizeParam.Winner::getUserId).collect(Collectors.toList()));
        convertActivityStatusDTO.setTargetUserStatus(ActivityUserStatusEnum.COMPLETED);
        activityStatusManager.handlerEvent(convertActivityStatusDTO);
    }
}
